Bacterial Fermentation

Abstract

Under anaerobic conditions, in the dark and in the absence of electron acceptors, organic compounds are catabolized by strictly
anaerobic or facultatively anaerobic bacteria by internally balanced oxidation–reduction reactions, a process called fermentation.
In fermentation, the organic compound serves as both electron donor and acceptor, and adenosine triphosphate is synthesized
by substrate‐level phosphorylation.

Generalized schemes for fermentation pathways. (a) A substrate is oxidized and the intermediate generated is reduced and excreted;
an example is homolactic acid fermentation. (b) The oxidized intermediate (e.g. pyruvate) is disproportionated leading to
a more complex product pattern, as observed in a variety of fermentations.

Figure 2.

Major pathways for fermentation of sugars including organisms involved and end products formed.